OUC staffers will conduct tours from noon to 4 p.m. They also will discuss the utility's energy conservation and budget-billing programs.

The plant is about 12 miles southeast of Orlando on the Alafaya Trail extension, which can be reached from State Road 50.

Construction began in October 1983. During the first open house in August, there was not a lot to see because most of the work had been horizontal, that is, limited to site clearing and the preparation of foundations.

Since then, construction has stretched skyward with the completion of the 23-story steel frame for the plant boiler. The steel skeleton for the generator and cooling tower are going up nearby. When completed, the tower's chimney will jut 550 feet into the air and dominate the landscape of the 5- square-mile site.

A $250,000 model depicting the plant at this stage of construction is at the site. Hardage said the 12-foot-high model has helped builders test the plant's design and work out space and logistical problems ahead of construction. Discovering that a single pipe will not fit into the space designed for it could save thousands of dollars, Hardage said.

Construction is ahead of schedule and the plant is expected to start operating in July 1987, two months earlier than planned.

The earlier operating date could save customers $12 million in lower costs for construction and fuel, said OUC representative Steve Willis.

OUC and 12 other utilities that are partners in the project insist that the plant will save their customers money in the long run.

The city of Kissimmee and the Florida Municipal Power Agency, a cooperative of small-city utilities, have agreed to buy 31.4 percent of the plant for about $112 million.